CN102903591A - Ultrafast lens-free coherent electron diffraction imaging method and device - Google Patents

Abstract

The invention discloses an ultrafast lensless coherent electron diffraction imaging method and device, which can analyze the diffracted coherent Intensity distribution of electron pulses, inversion calculation to determine electron scattering phase, realize three-dimensional transient atomic scale structure and shape reconstruction, solve the problem that traditional electron microscopy imaging methods do not have high time resolution or the current ultrafast electron imaging time and the technical dilemma of limited spatial resolution.

Description

Ultrafast lensless coherent electron diffraction imaging method and device

technical field

The present invention relates to time-resolved electron microscopy imaging, in particular to an ultrafast lensless coherent electron diffraction imaging method with a temporal resolution better than 1 picosecond and a spatial resolution better than 1 nanometer and a possible corresponding device.

Background technique

The background technology involved in the present invention is divided into two aspects;

1. The temporal and spatial resolution of the electron microscope: The traditional electron microscopic imaging has three main directions: increasing the electron accelerating voltage, using an electromagnetic lens, and improving the quality of the electron source, and its spatial resolution has been improved to the limit. Since traditional electron microscopic imaging is generally time-accumulated topography imaging, it is impossible to perform high-time-resolved imaging of processes in various fields such as physics, chemistry, and biology. Therefore, the introduction of time-resolution capability into traditional electron microscopy imaging technology is at the forefront of technological development in the world today. Among the existing time-resolved electronic imaging systems, the typical ultrafast electron microscopy (UEM) of the Zewail research group at the California Institute of Technology (Caltech) and the Lawrence Livermore National Laboratory (LLNL) The dynamic transmission electron microscope (DTEM) of Campbell's research group.

In these time-resolved electronic imaging systems, electron imaging from diffraction space (i.e., inverted space) to real space is realized by Fourier transform dominated by electromagnetic objective lens, since the electrons pass through the sample and use electromagnetic objective lens for imaging, the loss of electron Therefore, these systems are limited in the improvement of spatial resolution and temporal resolution. On the one hand, there are two major technical difficulties in improving the spatial resolution of electron beam electromagnetic lens imaging: one is that the aberration of the lens is required to be extremely small, otherwise the phase error will be introduced into the diffracted wave, and a clear image cannot be obtained. It is extremely difficult to achieve this with X-ray zone plate imaging; second, the entire experimental device must be stable enough so that large-angle electrons located at the edge of the diffraction plane can still interfere coherently at the image plane. Therefore, even with complex aberration correction, the usable angular range of general electron lenses is only 1-2 degrees. This limitation of momentum space (in other words, the maximum scattering range that the lens can accept the incident electron beam) seriously affects the spatial resolution. On the other hand, since electrons repel each other as charged particles, the pulse width of electrons will be broadened during the long-distance flight through the electromagnetic lens, resulting in a decrease in time resolution.

2. Coherent lensless diffraction imaging: It uses theoretical methods and computer algorithms to solve the phase problem of diffraction in samples with periodic and non-periodic structures. It is called coherent x-ray diffractive imaging (CXDI) in the X-ray field. ). Phase problems in the visible domain have been recognized very early, and Rayleigh once commented in a letter to Michelson that phase problems in interferometry cannot be solved without relevant information about the symmetry of the data. The successful solution of the phase problem is attributed to D. Sayre, who pointed out in 1952 that the relationship between Shannon's sampling theory and Bragg's law should be considered [Acta Crystallogr. 5, 843(1952)]. Subsequently, Gerchberg and Saxton wrote the algorithm for recovering the phase for the first time [Optik 35, 237 (1972)]. This algorithm is often called the hybrid input–output (HIO) algorithm [Appl. Opt. 21, 2758 (1982)]: iterates an original function in real space and Fourier space repeatedly, and each iteration performs real space Or Fourier space plus boundary conditions. This field began to develop rapidly around 1990. In 1999, Miao Jianwei et al. carried out experimental verification in the soft X-ray band for the first time [Nature 400,342(1999)]; The experimental research results of lens diffraction imaging [Science 300, 1419 (2003)], in 2008, Zhu Yimei and others proposed "position-sensitive diffractive imaging" (PSDI) for coherent lensless diffraction imaging of electrons. In the past 20 years, this technique has been widely used from crystallographic epitaxy to high-resolution imaging of amorphous samples [Adv. Phys. 59, 1 (2010)].

The basic principle of coherent electron diffraction imaging is to use the diffraction intensity of fitting electron diffraction to retrieve the phase information of the sample lost due to the lack of objective lens through reverse calculation. For coherent lensless imaging based on electron diffraction, the requirements for high stability of the device and energy dispersion of the incident beam are relatively relaxed. Coherent imaging does not require an objective lens, and directly uses a photosensitive film or a charge-coupled device (CCD) detector to record the intensity of the diffraction pattern. The advantage of diffraction imaging is that whether the interference conditions are satisfied is only determined by the scattering inside the sample itself, and does not require the electron beam to interfere after long-distance drift in the transmission system. However, similar to traditional electron microscopy imaging, this method is not yet time-resolved.

Therefore, the traditional electron microscopic imaging technology mainly has the following technical problems:

1. No time resolution capability or limited time resolution.

2. Low spatial resolution: The spatial resolution of real space images is restricted by the quality of the objective lens (such as aberration and chromatic aberration, etc.), and the cost of improving spatial resolution by using high-quality electromagnetic objective lenses is high.

3. High cost of improving time resolution: Although time resolution can be improved by using MeV electron pulses to suppress the problem of electron pulse broadening during flight, the cost of electromagnetic objectives is generally proportional to the energy of the focused electron beam ( About RMB 40 per electron volt), which will greatly increase the cost.

Contents of the invention

The object of the present invention is to overcome the shortcomings of the above-mentioned prior art, and provide an ultrafast lensless coherent electron diffraction imaging method and device. Compared with traditional electron microscopic imaging technology, ultrafast means that it has high time resolution, especially that it can achieve a time resolution better than 1 picosecond. It combines electron pulses precisely synchronized with process excitation sources (such as femtosecond laser pulses) and lens-free coherent diffraction imaging technology to analyze the intensity distribution of diffracted coherent electron pulses, determine the electron scattering phase through inversion calculation, and realize three-dimensional instantaneous The structure and shape reconstruction at the atomic scale solves the technical dilemma that the traditional electron microscopy imaging method does not have high time resolution or the current ultrafast electron imaging is limited in time and space resolution.

Technical solution of the present invention is as follows:

An ultra-fast lensless coherent electron diffraction imaging method, which is characterized in that: the method combines pump-probe technology and lensless coherent electron diffraction imaging to simultaneously realize transient imaging with ultra-high time resolution and ultra-high spatial resolution; The method uses a high-brightness coherent electron pulse precisely synchronized with the process excitation pulse as the detection source; after the detection electron passes through the sample, it does not pass through any electron optical system (ie, electromagnetic lens), and the coherent electron diffraction imaging pattern is directly collected by the detection system, thereby maintaining the electron's Scattering phase information; this method calculates the scattering phase information of electrons from the coherent electron diffraction imaging through data processing and 3D reconstruction system using the existing inversion calculation method, and realizes the structure and shape reconstruction of the three-dimensional transient atomic scale .

The ultrafast lensless coherent electron diffraction imaging device implementing the above ultrafast lensless coherent electron diffraction imaging method consists of a process excitation source, a pulse electronic system, a pulse electronic control system, a sample, a detection system, a data processing and three-dimensional reconstruction system and high The composition of the vacuum sample target chamber, the functions and positions of the above components are as follows:

The pulse electronic system, pulse electronic control system, sample and detection system are placed in the high vacuum sample target chamber, and the sample is placed on the five-dimensional adjustment frame in the high vacuum sample target chamber, wherein the pulse electronic system consists of The pulse electron source and its acceleration and shaping components are composed; the process excitation source generates a process excitation pulse, which is input into the high vacuum sample target chamber to excite the sample on the five-dimensional adjustment frame.

The pulsed electron source generates electron pulses that are precisely synchronized with the process excitation pulses, and the pulsed electrons are accelerated and shaped into high-brightness coherent pulsed electron beams, wherein the spatial coherence length is better than 50 nanometers, and the temporal coherence length is better than 50 nanometers. 50 nanometers; after the pulse electronic control system is focused and irradiated on the sample area excited by the process excitation pulse in the high-vacuum sample target chamber, after being diffracted by the sample, a series of mutually coupled or overlapping diffractions are formed pattern; the diffraction pattern is received by the detection system, including Bragg diffraction peaks and interference information between Bragg peaks; input to the data processing and three-dimensional reconstruction system, through the online fast Fourier method, from the diffraction pattern to find back phase.

The process excitation source includes a femtosecond laser light source, a beam splitter, a first variable optical path delay adjustment system composed of a first laser servo mirror, a second laser servo mirror and a first translation stage, a third laser servo It consists of a reflector, an optical parametric amplification laser conversion system, a fourth laser servo reflector, and a focusing lens.

The pulsed electronic system consists of the fifth laser servo mirror outside the high-vacuum sample target chamber, the second optical path delay adjustment system composed of the sixth laser servo mirror, the seventh laser servo mirror and the second translation stage, and the eighth laser servo mirror. It consists of a laser servo mirror, a femtosecond laser triple frequency device, an ultraviolet focusing lens, a metal film in a high-vacuum sample target chamber, and a multi-stage microwave accelerator.

The pulse electronic control system consists of a first deflection plate, a second deflection plate, a first electromagnetic lens, a first aperture, a second electromagnetic lens and a second aperture located in the high vacuum sample target chamber.

Along the laser advance direction of the femtosecond laser source is the beam splitter, which divides the femtosecond laser pulse output by the femtosecond laser source into a reflected beam and a transmitted beam; along the direction of the reflected beam The forward direction is sequentially reflected by the first laser servo mirror, the second laser servo mirror, the third laser servo mirror, the optical parameter amplification laser conversion system, and the fourth laser servo mirror, and then focused by the focusing lens Finally, pass through the high-vacuum sample target chamber to irradiate the sample on the five-axis sample adjustment frame; pass through the fifth laser servo mirror and the sixth laser servo mirror in sequence along the forward direction of the transmitted light beam , the seventh laser servo mirror, the eighth laser servo mirror, the femtosecond laser triple frequency device and the ultraviolet focusing lens are converted into 266nm laser pulses after focusing.

The 266nm laser pulse irradiates the metal film located in the high-vacuum sample target chamber, and generates pulsed electrons through the photoelectric effect. After the electronic focusing and collimating system composed of the lens, the first aperture, the second electromagnetic lens and the second aperture, a coherent electron spot of about 50 nanometers or smaller is formed, which is irradiated in the sample area, and the Bragg diffraction formed by diffraction The diffraction pattern of the interference information between the peak and the Bragg peak, the diffraction pattern is received by the detection system, the data is processed by the data processing and three-dimensional reconstruction system, and the "position-sensitive diffraction imaging" (PSDI) technology is used to analyze The scattering phase information of the sample is obtained.

The process excitation pulses and the electron pulses are precisely synchronized by pump-probe technology.

The five-axis sample adjustment rack has up and down, front and rear, left and right, rotation and tilt adjustment postures.

The first variable optical path delay adjustment system formed by the first laser servo mirror and the second laser servo mirror being arranged on the first translation stage, the sixth laser servo mirror and the seventh laser servo mirror The second optical path delay adjustment system formed on the second translation stage.

The principle of technical solution of the present invention:

1. Solve the problem of no time resolution capability or limited time resolution: use electron pulses, especially MeV femtosecond electron pulses, which are precisely synchronized with the process excitation source (such as femtosecond laser).

2. Solve the problem that the spatial resolution is limited by the quality of the objective lens: use lensless coherent electron diffraction imaging, do not use the objective lens (that is, the defocusing electromagnetic lens), and shorten the electron flight distance.

3. Solve the high-cost problem of improving time resolution by using megaelectron-volt electron pulses: use lensless coherent electron diffraction imaging, without using an objective lens, and greatly reduce costs.

4. Achieve ultra-high spatial resolution: Due to the use of high-brightness coherent electron beams (the spatial coherence length is better than 50 nanometers, and the temporal coherence length is better than 50 nanometers) and tightly focused electron optics (the focused electron spot is less than 50 nanometers), the electron scattering phase is guaranteed The inversion of , so that the technique can achieve a spatial resolution better than 1 nanometer.

5. Achieve ultra-high time resolution: Ultrafast (i.e., time-resolved) electron microscopy imaging can detect the lensless coherent electron diffraction pattern at each relative moment by precisely adjusting the time delay between the process excitation pulse and the detection electron pulse, and The inversion at this moment and the three-dimensional reconstruction of the sample are carried out to finally obtain the transient structure information before and after the pump excites the sample region. Time resolution better than 1 picosecond can be achieved by controlling the process excitation pulse, the probe electron pulse width, and the synchronization between the two with an accuracy of less than 1 picosecond.

Compared with prior art, the beneficial effect of the present invention is:

1. Transient imaging with ultra-high time resolution and ultra-high spatial resolution: it utilizes high-energy electron pulses precisely synchronized with process excitation sources (such as lasers), combined with pump-probe methods, and can simultaneously achieve ultra-high time resolution (better than 1 picosecond) and ultra-high spatial resolution (better than 1 nanometer) transient imaging capabilities.

2. Avoid the limitation of electromagnetic lens to improve the time resolution: its lensless design avoids the pulse broadening of the femtosecond detection electron pulse after passing through the electron lens, maintains the electron pulse width, and ensures the time resolution of the method.

3. Greatly reduce costs: Its lensless design, simple structure, avoids the use of expensive defocusing electromagnetic lenses.

4. Provides important local transient structural information that time-resolved electron diffraction lacks.

Description of drawings

Fig. 1 is a schematic diagram of the structure of the ultrafast lensless coherent electron diffraction imaging device of the present invention.

Fig. 2 is a schematic structural view of an embodiment of the device of the present invention.

Detailed ways

The present invention will be further described below in conjunction with the embodiments and accompanying drawings, but the protection scope of the present invention should not be limited thereby.

The ultra-fast lensless coherent electron diffraction imaging method of the present invention has the advantages of simple pulse electronic control system, and the spatial resolution is not restricted by the defocusing objective lens. It only needs a set of strong focusing magnetic lenses to focus the pulse electrons on the sample, without By defocusing the electromagnetic lens, ultra-high time and ultra-high spatial resolution in real space can be realized. This method is very easy to combine with MeV ultrafast electron diffraction, but this method has extremely high requirements on the coherence of the pulsed electron beam. The coherence of the pulsed electron beam and the focused electron spot size determine the spatial resolution of the present invention.

The electronic pulse used in the ultrafast lensless coherent electron diffraction imaging method of the present invention is precisely synchronized with the process excitation source; the pulse width of the detection electronic pulse, the pulse width of the process excitation pulse, and the synchronization accuracy of the electronic pulse and the process excitation source etc. determine the time resolution capability of the method, and a time resolution of 1 picosecond or even better can be achieved.

Please refer to FIG. 1 first. FIG. 1 is a schematic structural diagram of an ultrafast lensless coherent electron diffraction imaging device of the present invention. The ultrafast lensless coherent electron diffraction imaging device of the present invention consists of a process excitation source 01, a pulse electronic system 02, a pulse electronic control system 03, a sample 04, a detection system 05, a data processing and three-dimensional reconstruction system 06 and a high vacuum sample target chamber 07, the functions and positional relationship of the above components are as follows:

The pulse electronic system 02, the pulse electronic control system 03, the sample 04 and the detection system 05 are placed in the high vacuum sample target chamber 07, and the sample 04 is placed on the five-dimensional adjustment frame in the high vacuum sample target chamber 07, The pulsed electron system 02 is composed of a pulsed electron source and its acceleration and shaping components; the process excitation source 01 generates a process excitation pulse, which is input into the high vacuum sample target chamber 07 to excite the five-dimensional adjustment Sample 04 on shelf.

The pulsed electron source generates electron pulses that are precisely synchronized with the process excitation pulses. The pulsed electrons are accelerated and shaped into high-brightness coherent pulsed electron beams, which are focused and irradiated at a high temperature by the pulsed electronic control system 03 The sample area excited by the process excitation pulse in the vacuum sample target chamber 07 is diffracted by the sample to form a series of mutually coupled or overlapping diffraction patterns; the diffraction patterns are received by the detection system 05, Including Bragg diffraction peaks and interference information between Bragg peaks; input to the data processing and three-dimensional reconstruction system 06, and retrieve the phase from the diffraction pattern through the online fast Fourier method.

Please refer to FIG. 2 . FIG. 2 is a schematic structural diagram of an embodiment of the device of the present invention. The embodiment is a device with a femtosecond pulsed laser as the process excitation source. As can be seen from the figure, the composition of the ultrafast lensless coherent electron diffraction imaging device of the present invention:

The process excitation source 01 includes a femtosecond laser light source 1, a beam splitter 2, a first variable optical path delay adjustment composed of a first laser servo mirror 3, a second laser servo mirror 4 and a first translation stage 5 system, the third laser servo mirror 6, the optical parameter amplification laser transformation system 7, the fourth laser servo mirror 8, and the focusing lens 9.

The pulsed electronic system 02 is composed of the fifth laser servo mirror 10 located outside the high vacuum sample target chamber 24, the sixth laser servo mirror 11, the seventh laser servo mirror 12 and the second translation stage 13. The second optical path delay adjustment system, the eighth laser servo mirror 28, the femtosecond laser triple frequency device 14, the ultraviolet focusing lens 15, the metal film 16 located in the high vacuum sample target chamber 24 and the multi-stage microwave accelerator 17 are composed.

The pulse electronic control system 03 consists of the first deflection plate 18, the second deflection plate 19, the first electromagnetic lens 20, the first aperture 21, the second electromagnetic lens 22, and the second aperture 23 located in the high vacuum sample target chamber 24. constitute.

Along the laser advance direction of the femtosecond laser light source 1 is the beam splitter 2, which divides the femtosecond laser pulse output by the femtosecond laser light source 1 into a reflected beam A and a transmitted beam B; The forward direction of the reflected light beam A passes through the first laser servo mirror 3, the second laser servo mirror 4, the third laser servo mirror 6, the optical parameter amplification laser conversion system 7, the fourth laser servo Reflected by the mirror 8, after being focused by the focusing lens 9, the sample located on the five-axis sample adjustment frame 25 is irradiated through the high-vacuum sample target chamber; After the fifth laser servo mirror 10 described above is focused by the sixth laser servo mirror 11, the seventh laser servo mirror 12, the eighth laser servo mirror 28, the femtosecond laser triple frequency device 14 and the ultraviolet focusing lens 15 Converted to 266nm laser pulses.

The 266nm laser pulse irradiates the metal film 16 located in the high-vacuum sample target chamber 24, and generates pulsed electrons through the photoelectric effect, and the pulsed electrons are deflected by the multistage microwave accelerator 17, the first deflection plate 18, and the second deflection plate. The plate 19, the electronic focusing and collimation system composed of the first electromagnetic lens 20, the first aperture 21, the second electromagnetic lens 22, and the second aperture 23 are then irradiated in the sample area, and the Bragg diffraction peaks formed by diffraction and Diffraction pattern of Bragg inter-peak interference information, the diffraction pattern is received by the detection system 26, sent to the data processing and three-dimensional reconstruction system 27 for data processing, using the "position-sensitive diffraction imaging" (PSDI) technology, Analyze the scattering phase information of the sample.

The process excitation pulses and the electron pulses are precisely synchronized by pump-probe technology.

The five-axis sample adjustment rack has up and down, front and rear, left and right, rotation and tilt adjustment postures.

The first variable optical path delay adjustment system formed by the first laser servo mirror 3 and the second laser servo mirror 4 being arranged on the first translation stage 5, the sixth laser servo mirror 11 and the seventh laser servo mirror The laser servo mirror 12 is arranged on the second translation stage 13 to form a second optical path delay adjustment system.

Among them, the high-vacuum sample target chamber where the sample is placed, the chamber of the pulsed electron source, the chamber of the pulsed electronic control system, and the chamber of the detection system are all in a high-vacuum or ultra-high-vacuum environment, which can be pumped by the front-stage mechanical pump and molecular pump. to below 10 ^-7 Pa, and then maintain an ultra-high vacuum state through an ion pump and a sublimation pump.

The ultra-fast (i.e. time-resolved) lensless coherent electron diffraction imaging (i.e. electron microscopic imaging) described in the present invention can adjust the distance between the pump pulse and the detection electron by precisely adjusting the first translation stage 5 or the second translation stage 13 time delay, and then detect the lensless coherent electron diffraction pattern at each relative time, and carry out the inversion and three-dimensional reconstruction of the sample at this time, and finally obtain the transient structure information before and after the pump excites the sample area. Since the process excitation pulse is at the femtosecond level, the process excitation pulse and the detection electron pulse have the same source (accurate synchronization to the femtosecond level can be achieved), as long as the detection electron pulse width is controlled below 1 picosecond and the movement accuracy of the translation stage Time resolution better than 1 picosecond can be achieved at better than 150 microns.

The coherently diffracted electron pulses in the present invention require certain spatial and temporal coherence. The spatial and temporal coherence of the electron pulses determines the operability and spatial resolution of the method. Based on the current 3 MeV ultrashort electron source, the spatial coherence length can reach 30 nanometers, and the temporal coherence length can reach 0.5 nanometers, which can meet the requirements of femtosecond electron diffraction. In order to realize ultrafast lensless coherent electron diffraction imaging, it is necessary to further optimize the ultrashort MeV electron pulse, so that the energy dispersion can be reduced from 10 ^-3 to 10 ^-5 , thereby increasing the time coherence length of electrons by two orders of magnitude, while reducing the The divergence angle is used to increase the spatial coherence length by more than 3 times, so that through the imported double focusing mirror and the aperture of the focusing mirror, the ultrafast electron beam spot can be focused to 30-50 nanometers, and it is expected to achieve 1 nanometer for nanoparticles and ultra-thin samples. Spatial resolution, so as to achieve ultra-high time resolution and ultra-high spatial resolution at the same time.

Claims (8)

1. One kind ultrafast without the relevant electronic diffraction formation method of lens, it is characterized in that: the method is in conjunction with the pumping-detection technology with without the relevant electronic diffraction imaging of lens, to realize simultaneously the transient state imaging of ultrahigh time resolution and superelevation spatial discrimination; The method adopts with the relevant electronic impulse of the high brightness of process excitation pulse precise synchronization as detection source; Directly collect relevant electronic diffraction imaging pattern by detection system after surveying electronics process sample, thereby keep the scattering phase information of electronics; The method utilizes existing Inversion Calculation method to calculate the scattering phase information of electronics from described relevant electronic diffraction imaging by data processing and three-dimensional reconfiguration system, realizes structure and the pattern reconstruct of Three dimensional transient atomic scale.
2. 2. according to claim 1 ultrafast without the relevant electronic diffraction formation method of lens, it is characterized in that adopting the coherent electron beam of high brightness, its Spatially coherent length is better than 50 nanometers, temporal coherent length is better than 50 nanometers, as detection source and tight focused electron optics, guarantee the inverting of electron scattering phase place, thereby make this technology can realize being better than the spatial resolution of 1 nanometer.
3. 3. according to claim 1 ultrafast without the relevant electronic diffraction formation method of lens, it is characterized in that the ultrashort electronic impulse of employing and process excitation pulse precise synchronization is as detection source; By the control procedure excitation pulse, survey electronic impulse width and synchronization accuracy between the two all below 1 psec, can realize being better than the temporal resolution of 1 psec.
4. 4. the pulse duration of electronic impulse, the pulse duration of process excitaton source, electronic impulse are the temporal resolutions that synchronization accuracy etc. with the process excitaton source has determined the method.
5. 5. implement each described ultrafast ultrafast without the relevant electronic diffraction imaging device of lens without the relevant electronic diffraction formation method of lens of claim 1-3, it is characterized in that, this device is comprised of process excitaton source (01), pulsed electron system (02), pulsed electron control system (03), sample (04), detection system (05), data processing and three-dimensional reconfiguration system (06) and high vacuum sample target chamber (07), and function and the position relationship of above-mentioned component are as follows:

   Described pulsed electron system (02), pulsed electron control system (03), sample (04) and detection system (05) place in the described high vacuum sample target chamber (07), sample (04) places five in the high vacuum sample target chamber (07) to tie up on the adjustment racks, described pulsed electron system (02) is comprised of Pulse Electric component and acceleration thereof, reshaping device, described process excitaton source (01) production process excitation pulse is inputted described high vacuum sample target chamber (07) and is excited the sample (04) that is positioned on the described five dimension adjustment racks;

   Described Pulse Electric component produces the electronic impulse with described process excitation pulse precise synchronization, this pulsed electron becomes the relevant pulsed electron beam of high brightness through acceleration, shaping, focusing is radiated at the sample area that is excited by the process excitation pulse that is in the high vacuum sample target chamber (07) through described pulsed electron control system (03), behind described sample diffraction, form a series of that intercouple or overlapped diffraction patterns; This diffraction pattern is received by described detection system (05), comprises the interference information between Bragg diffraction peak and bragg peak; Input described data and process and three-dimensional reconfiguration system (06), by online fast Fourier method, from diffraction pattern, give phase place for change.
6. 6. according to claim 2 ultrafast without the relevant electronic diffraction imaging device of lens, it is characterized in that described process excitaton source (01) comprises that femtosecond laser light source (1), beam splitter (2), the first changeable optical path that is made of the first laser servo speculum (3), the second laser servo speculum (4) and the first translation stage (5) postpone regulating system, the 3rd laser servo speculum (6), optical parameter amplifying laser conversion system (7), the 4th laser servo speculum (8), condenser lens (9) formation;

   The second optical path delayed regulating system, the 8th laser servo speculum (28), femtosecond laser frequency tripling device (14), ultraviolet condenser lens (15) that described pulsed electron system (02) consists of by the 5th outer laser servo speculum (10) of high vacuum sample target chamber (24), by the 6th laser servo speculum (11), the 7th laser servo speculum (12) and the second translation stage (13), and be positioned at high vacuum sample target chamber (24) metal film (16) and multistage microwave accelerator (17) formation successively;

   Described pulsed electron control system (03) is by being positioned at successively the first deflector (18) of high vacuum sample target chamber (24), the second deflector (19), being made of the first electromagnetic lens (20), the first aperture (21), the second electromagnetic lens (22), the second aperture (23);

   Laser direction of advance along described femtosecond laser light source (1) is described beam splitter (2), and this beam splitter (2) is divided into folded light beam (A) and transmitted light beam (B) with the femto-second laser pulse of femtosecond laser light source (1) output; Direction of advance along described folded light beam (A) reflects through described the first laser servo speculum (3), the second laser servo speculum (4), the 3rd laser servo speculum (6), optical parameter amplifying laser conversion system (7), the 4th laser servo speculum (8) successively, after described condenser lens (9) focuses on, pass described high vacuum sample target chamber and shine the sample that is positioned on the five axle sample adjusting brackets (25); Pass through successively described the 5th laser servo speculum (10), be converted into the 266nm laser pulse after being focused on by the 6th laser servo speculum (11), the 7th laser servo speculum (12), the 8th laser servo speculum (28), femtosecond laser frequency tripling device (14) and ultraviolet condenser lens (15) along the direction of advance of described transmitted light beam (B);

   Described 266nm laser pulses irradiate is positioned on the metal film (16) of described high vacuum sample target chamber (24), and by photoelectric effect generation pulsed electron, this electronic impulse is through multistage microwave accelerator (17), the first deflector (18), the second deflector (19), by the first electromagnetic lens (20), the first aperture (21), the second electromagnetic lens (22), be radiated in the described sample area behind the electron focusing colimated light system that the second aperture (23) consists of, the diffraction pattern of interference information between the Bragg diffraction peak of diffracted formation and bragg peak, this diffraction pattern is received by described detection system (26), send into described data processing and three-dimensional reconfiguration system (27) and carry out the data processing, parse the scattering phase information of sample.
7. 7. according to claim 3 ultrafastly it is characterized in that without the relevant electronic diffraction imaging device of lens is about described five axle sample adjusting brackets have, all around, rotation and tilt adjustments attitude.
8. 8. according to claim 3 ultrafast without the relevant electronic diffraction imaging device of lens, it is characterized in that, described the first laser servo speculum (3) and the second laser servo speculum (4) are arranged at upper the first changeable optical path that consists of of the first translation stage (5) and postpone regulating system, and described the 6th laser servo speculum (11) and the 7th laser servo speculum (12) are arranged at upper the second optical path delayed regulating system that consists of of the second translation stage (13).

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